Sources say clandestine discussions have been going on for two months in neighbouring Oman, news agency says.

Saudi officials and Houthi rebels have held months of secret talks on ending Yemen's devastating three-year war, according to a news report.

The warring parties discussed ways to halt the conflict that has left 22 million Yemenis in dire need of humanitarian assistance, diplomats and Yemeni officials told Reuters news agency on Thursday.

The war has killed an estimated 10,000 people, left millions facing famine, and initiated a major outbreak of disease.

The sources - speaking on condition of anonymity - said Houthi spokesman Mohammed Abdul-Salam had met with Saudi officials in neighbouring Oman.

"There are consultations between the Houthis and the Saudis, without a representative of the internationally recognised government, and it is clear that there is a desire of the Houthis and the coalition to go toward a comprehensive agreement," a diplomat was quoted as saying.

Wrap it up

The resolution of the conflict would begin with a truce that would halt fighting and allow the negotiation of a definitive peace deal that accounts for the interests of both sides, sources said.

The diplomats told Reuters the talks have been going on for two months. The negotiations follow previous mediation efforts between the Yemeni government and the Houthis that were held in Kuwait in 2016.

Both sides have yet to comment on the news report.

Saudi Arabia, which is leading a military coalition against the rebels, launched its intervention in Yemen to reinstate the internationally recognised government of President Abu-Rabbu Mansour Hadi.

Coalition air strikes have failed to bring about any real change on the battleground where Houthis continue to control the capital, Sanaa, and most of northern Yemen.

Thousands of Saudi-led air strikes have killed hundreds of Yemeni civilians. Coalition forces have made modest territorial gains, but appear far from seizing back the capital from seasoned fighters.

With no victory in sight, and as the war pushes the country towards famine, Saudi officials - including the powerful Crown Prince and Defence Minister Mohammed bin Salman - have expressed a desire to wrap up the conflict.

'Devastating' conditions

The UN Security Council said on Thursday that 22.2 million people - of a 27.5 million Yemenis - are in need of humanitarian assistance, a 3.4 million jump compared to last year.

The council expressed concern over indiscriminate attacks on densely populated areas that have led to high civilian casualties and significant damage to civilian infrastructure.

"The Security Council expresses its grave concern at the continued deterioration of the humanitarian situation in Yemen, and the devastating humanitarian impact of the conflict on civilians," it said in a statement.

The UNSC called on all parties to "respect and protect schools, medical facilities, and personnel".

It also denounced the use of schools by rebels as arms depots and condemned "in the strongest possible terms" ballistic missile attacks by the Houthis on Riyadh in November and December 2017.